java实战 jvm调优

🧙 Questions

对java虚拟机调优和优化

☄️ Ideas

运行参数说明

参数名	描述	配置
-Xmx	最大可使用内存	2048m 或者 1664299798
-Xms	项目运行初始化使用内存	512m 或者 1664299798

jvm常用命令

# 查看java进程，只看进程的文件名和pid
jps 
# 查看进程的文件全路径和pid
jps -l
# 查看进程的详细执行命令
jps -lv

# 查看进程内存使用详情
# jmap -heap ${pid}


Debugger attached successfully.
Server compiler detected.
JVM version is 25.292-b10

using thread-local object allocation.
Parallel GC with 8 thread(s)

Heap Configuration:
   MinHeapFreeRatio         = 0
   MaxHeapFreeRatio         = 100
   MaxHeapSize              = 2147483648 (2048.0MB)
   NewSize                  = 346030080 (330.0MB)
   MaxNewSize               = 715653120 (682.5MB)
   OldSize                  = 692060160 (660.0MB)
   NewRatio                 = 2
   SurvivorRatio            = 8
   MetaspaceSize            = 21807104 (20.796875MB)
   CompressedClassSpaceSize = 1073741824 (1024.0MB)
   MaxMetaspaceSize         = 17592186044415 MB
   G1HeapRegionSize         = 0 (0.0MB)

Heap Usage:
PS Young Generation
Eden Space:
   capacity = 620232704 (591.5MB)
   used     = 3022304 (2.882293701171875MB)
   free     = 617210400 (588.6177062988281MB)
   0.4872854947036137% used
From Space:
   capacity = 48234496 (46.0MB)
   used     = 0 (0.0MB)
   free     = 48234496 (46.0MB)
   0.0% used
To Space:
   capacity = 47185920 (45.0MB)
   used     = 0 (0.0MB)
   free     = 47185920 (45.0MB)
   0.0% used
PS Old Generation
   capacity = 1419771904 (1354.0MB)
   used     = 96972344 (92.48003387451172MB)
   free     = 1322799560 (1261.5199661254883MB)
   6.830135441249019% used

🔗 Links

• java website